Episodes 1.1-1.24 originally released as a Christmas calendar on www.gubi.com on December 1-24, 1999. The New Year's Episode was originally released on www.gubi.com on December 31, 1999.
25 episodes were shot for the 24 episode Christmas calendar run so www.gubi.com could reject one of them. The missing episode (1.25) was never released on the Internet, and is available only on the first R2 DVD collection of Casper & Mandrilaftalen (1999) (released on 7 March 2002 by CMC Records A/S).
All 26 episodes available on the first R2 DVD collection of Casper & Mandrilaftalen (1999) (released on 7 March 2002 by CMC Records A/S).
Entire footage was filmed during 1 ½ days in November 1999.